Ground Quartz Stone- This is in a powdered form and is obtained from the nearest market. Since it is the main raw material, it is normally bought in tons. The cost of quartz stone is about Rs. 1200 - 1300 per ton.
Glass Powder- Green glass which is normally used in making tea glasses is taken into use. Broken pieces of glass are available with the 'Kabaadi' (a waste material collector) and costs around Rs. 4-5 per kilogram. The obtained glass is first treated before being used for the dough. The treatment involves thorough washing of the glass, breaking it into fine pieces and then grinding it into powder in the grinding machine.
Katira Gond (kind of adhesive)- It is obtained from the market in big pieces and costs Rs. 80-85 per kilogram. Before use, the pieces are broken by hand, ground into powder with a grinding machine and sieved with an iron sieve.
Tragacanth Gond- It is can be obtained from a regular grocer's shop and costs about Rs.150 per kilogram. It is available in the form of grains and needs to be ground up before use.
Fullers Earth (Multani Mitti)- It is available in the market in small pieces and costs about Rs. 8 - 10 per kilogram.
Saaji (soda bicarbonate/ bentonite)- It is available in the market in the form of small pieces and costs about Rs. 40-50 per kilogram. Broken pieces of 'Multani Mitti' and 'Saaji' are taken in equal proportions and then ground to a powdered form in the grinding machine. It takes approximately five days to prepare a 50 kilogram mixture of Multani Mitti and Saaji.
Flour- Refined white flour made of wheat known as 'Maida' can be obtained easily from the market and is used as an adhesive in the process of blue pottery.
Colors- The colors used in blue pottery are of two types: oxide colors and ferro colors. The usual oxides used for coloring are cobalt oxide (for dark blue color), copper oxide (for light blue color), chrome oxide (for green color), cadmium oxide (for a bright yellow color). The Ferro colors are used for the colors brown and yellow.
Borax- It is available in the market at the cost of Rs. 3500 - 4000 per 50 kilogram.
Zinc Oxide, potassium nitrate and boric acid.-These are easily obtained from the market.
Water- It is used in binding and forming the dough.
Tools & Technology
Chakki (Grinding Machine) - It is a grinding tool made of stone. In this, one stone rotates over the other stone and the material is poured from above. On rotating the wheels, the material reaches between the two stones and is ground through friction. It is a manual use machine in which the upper stone is rotated by hand. Nowadays, mechanical machines are taking its place.
Molds- These are made of clay or a quartz mixture and are used to give shape to the products. Molds in several shapes are prepared for different items and one mold can be used several times.
Flattening Tool- It is made of terracotta clay and is used to flatten the dough prepared for blue pottery.
Sand Paper- It is used for giving a smooth polished finish to the products.
Iron Blade or Knife- It is used for cutting the dough and scooping the portions of pottery items. It is bent at a right angle so that the scooping can be done easily.
Base Stone- The base stone is a smooth stone block where the polishing of the pots or other items is done by rubbing them on the stone.
Broom- It is a very small broom made of husk.
Potter's Wheel- It is a wheel used by potters for shaping utensils and consists of a big circular stone pivoted at the center of the wheel which is rotated by an iron pipe.
Brushes- The brushes are made by the craftsman using squirrel hair. These are used for coloring and making designs on the various pottery products.
Heating Kiln- A heating kiln is made of clay and brick and is a closed kiln. It is usually circular in shape and about 40 to 50 items of blue pottery can easily be put inside the kiln. It is heated by charcoal or wood and can be heated to the temperature of 800 to 900 degrees Celsius. The wood and charcoal are moved below the kiln by long iron rods.
The dough used for molding is prepared by mixing five ingredients. These are quartz stone powder (40 kilograms) which is the major item, powdered glass (5 kilograms), Katira gond powder (1 kilogram) and a mixture of multani mitti and saaji (1kilogram). These are put on the hard floor and are thoroughly mixed till the mixture becomes homogeneous. After that, water (25 liters) is mixed into it till a smooth non-sticky dough is made. The dough is rested for 8 - 10 hours.
A small amount of prepared dough is taken and then rolled by hand on the base stone. It is cut in equal parts (using a) according to the item being prepared. After this the dough is flattened with the help of a flattening tool till it takes the form of a 4 - 5 millimeter thick 'Chapatti' (pancake). The 'Chapatti' is carefully put into the mold which is shaken lightly so that the chapatti sets in the mold. After that, a mixture of fine 'Bajri' (stones) and 'Raakh' (ash made from burnt wood) is put into the mold and is lightly pressed so that the dough takes the exact shape of the mold. The extra dough is cut off with a knife. The mold is then turned upside down on the base stone and removed. The dough made with bajri and raakh, is left to dry for one to two days.
The dried dough is now in the shape of the mold. It is again turned upside down and the raakh and bajri mix is removed from it. During the process of drying, some raakh sticks to the pottery item. It is cleaned with the help of a small broom made from husk.
Once the pottery item is ready; it is rubbed lightly by hand on the base stone to even out the edges. After doing this, the pot becomes evenly shaped.
Except for tiles and wall hangings, most of the pottery items are prepared in two or more parts. After the molded item is ready, a base is added below it. In rounded pots, it is done by putting it on the potter's wheel. The wheel is set in motion and the pot is fixed at the center of the wheel. A little amount of dough is taken and with a touch of water, the base of the vessel is added. It is again left for drying for one to two days.
The pot is now ready in form. It is rubbed with 'Regmaal' to polish the surface. A little amount of wet dough is taken and applied on the vessel. It is removed with a knife thereby burnishing the vessel. The process is repeated two to three time still the vessel becomes absolutely even. It is then left for drying. After it dries, it is again rubbed with sandpaper.
After this process a solution of quartz powder (10 kilograms), powdered glass (3 kilograms), edible flour (maida) and water is made. The vessel is dipped in this solution and taken out in such a way that it is evenly coated. It is then left to dry.
A design is made on the dried, coated vessel with a solution of cobalt oxide and edible gum. The initial rings on the vessel (if circular) are made by keeping it on the potter's wheel and touching the brush tip on the vessel. The later intricate design is then made by brushes of varying thicknesses.
Once the design of the vessel is complete; the coloring is done by using oxides of various metals. These oxides are mixed with edible gum and then ground on the stone. The color is carefully filled with a brush. The vessel is left for drying.
After this, a coating of glaze is done on the vessel. The mixture of glaze is prepared by mixing the following things in their respective proportions: Powdered glass (21 kilograms), borax orsuhaaga (17.5 kilograms), zinc oxide (1.5 kilograms), potassium nitrate (2.5 kilograms) and Boric acid (7.5 kilograms). This mixture is heated in the kiln till it melts. On cooling, the mixture transforms into small pebbles. It is then ground to a powdered form in the grinding machine. The mixture is mixed with water and maida (used as an adhesive). The solution is then coated on to the vessel.
Finally, the prepared vessels are heated in the closed kiln fuelled with charcoal for four to five hours at temperatures of 800 to 850 degrees Celsius. Most of the material melts, but 80 per cent of the quartz is left behind, and this maintains the form of the vessel. The kiln is left to cool for three days, avoiding any rapid temperature change which cracks the china very easily. Care is taken that no two vessels touch each other as they may turn black. After cooling, the vessels are taken out and are ready for sale.